This invention relates to tufting machines and more particularly to tufting apparatus for forming selective rows of loop pile stitching in a cut pile tufting machine.
In a tufting machine a plurality of rows of yarn carrying needles are reciprocably driven through a base fabric fed through the machine to form loops to be seized by loopers oscillating below the fabric in timed relationship with the needles as the loopers cross the needles just above the needle eye. In loop pile machines the loopers point in the direction in which the base fabric is being fed, and hold the seized loops while the needles are being retracted from the fabric, thereafter moving away from the point of seizure to release the loop. In conventional cut pile machines the loopers (or hooks) point in the direction opposite to the direction of fabric feed so the loops feed into the loopers and each looper cooperates with a respective oscillating knife. Since the loops are being fed toward the closed end of the looper they cannot be released except by being cut by the knife. As the looper rocks away from the point of loop seizure the knife rocks upwardly and cuts the loop between the top edge of the knife and the bottom edge of the looper.
It is known to form spaced rows of cut pile and loop pile in a tufting machine by a number of methods. For example, in Card U.S. Pat. No. 3,084,645 cut pile and loop pile in the same row of stitching can be formed selectively using a looper pointing in the direction oppositely to fabric feed, the looper having a spring clip which permits a loop to be withdrawn from the looper by backdrawing yarn to force the clip away from the looper. The loops withdrawn remain uncut while those loops that remain on the looper are cut. A yarn feed pattern attachment must be utilized to effect selectively the backdrawing. Thus, although each row of stitching may be controlled to form either cut pile or loop pile, this apparatus, because of the backdrawing, produces uncut loops having a pile height shorter than the cut pile produced.
In Card et al U.S. Pat. No. 3,919,953 a tufting machine is disclosed in which adjacent rows of loopers point in the opposite direction to each other to form alternate rows of cut pile and loop pile. The rows of loopers which produce loop pile point in the same direction in which the base fabric is being fed, while the hooks in the rows producing cut pile point in the opposite direction and cooperate with a respective knife. Thus, although mounted in a single tufting machine bed, the loop pile producing members and the cut pile producing members operate in conventional manner and can be positioned below the bedplate to produce even level cut and loop pile. The difficulty presented, however, is that two looper bars are required, one slotted for the loop pile loopers and the other for the cut pile loopers. Thus, if a fabric having anything but a row of cut pile intermediate each row of loop pile is desired, it cannot be produced by this apparatus.
In Jolley et al U.S. Pat. No. 4,134,347 and Inman U.S. Pat. No. 4,185,569 tufting machines are illustrated in which level cut pile and loop pile may be formed in the same row of stitching selectively, and thus each row may form either cut pile or loop pile. These machines utilize gate controlled loopers for selectively opening and closing passage of a loop onto the blade of the looper, and although they provide versatile patterning capabilities their sophistication may not be warranted where the type of pile in a given row remains basically fixed.
In Ingram et al copending U.S. application Ser. No. 174,119 filed July 31, 1980, and commonly assigned to the assignee of the present invention, a uniquely designed looper is disclosed which seizes and thereafter releases a loop when pointing in the direction oppositely to the direction the base material is being fed, i.e. when installed in a cut pile tufting machine. Such a looper can be used to form selective arrays of loop pile and cut pile rows.